1. Field of the Invention
This invention relates to a toner collecting apparatus for collecting a developing agent, i.e. a toner, remaining on a photoconductive member of an image forming apparatus such as an electrophotographic copying machine and a laser printer.
2. Description of the Prior Art
An image forming apparatus, like an electrophotographic copying machine and a laser printer, is equipped with a toner collecting apparatus. The toner collecting apparatus is for collecting a developing agent (hereinafter referred to as a toner) left and removed off a photoconductive drum after transferring a toner image formed on the photoconductive drum onto a plain paper.
A first example of the conventional toner collecting apparatuses is shown in FIG. 5. This toner collecting apparatus has a support plate 11 and a toner collecting container 12 placed on the support plate 11. The support plate 11 is held swingably with a shaft at one end 11a, and hooked to a spring 14 at the other end 11b. Toner removed off a photoconductive drum is transferred through a conveyor pipe 15, and collected in the toner collecting container 12. The strength of the spring 14 is so set that it brings the end 11b of the support plate 11 into contact with a stopper 16 till the toner collecting container 12 is filled up with the collected toner. When the toner collecting container 12 is full, the spring 14 extends and the support plate 11 inclines to a predetermined position. And when the support plate 11 inclines to the predetermined position, the support plate 11 presses and turns on a switch 13. Then, a signal is generated to display an alarm on an operation panel or to prohibit a copying operation.
This first conventional toner collecting apparatus arouses an operator's attention with the alarm display or the prohibition of copying operation when the toner collecting container 12 is substantially filled up with the collected toner. However, the alarm display or the prohibition of copying operation is not given when an operator fails to place the toner collecting container 12 on the support plate 11. Consequently, the toner collected is spilled to contaminate inside a copying apparatus.
A second example of the conventional toner collecting apparatuses is shown in FIG. 6. This toner collecting apparatus has a support rest 21 and a toner collecting container 22 made of a transparent or semitransparent material such as polyethylene and placed on the support rest 21. A photoelectric switch 23 made of a light emitting element 23a and a light receiving element 23b is disposed at the neck of the toner collecting container 22. When the toner collecting container 22 is substantially full, the photoelectric switch 23 is turned off to generate a signal for displaying an alarm on an operation panel or prohibiting a copying operation. The support rest 21 has a lever 24 having an inverted "L"-shape. And the lever 24 has a stopper 24a at the rear and a corner joined to a support shaft 24b. When the toner collecting container 22 is placed at a predetermined position, the toner collecting container 22 presses the stopper 24a and the lever 24 swings upward around the support shaft 24b from a position shown with alternate long and two dashes lines to a position shown with solid lines. The lever 24 is placed in a manner overlapping a side of the support rest 21, i.e. a position shown with the alternate long and two dashes lines, when the toner collecting container 22 is not on the support rest 21. An end 24c of the lever 24 protrudes slightly ahead of an end surface of the support rest 21. The end 24c of the lever 24 blocks and prevents a cover (not shown), which is opened and closed when replacing the toner collecting container 22, from being locked in place.
This second conventional toner collecting apparatus detects the toner collecting container 22 filled up with the collected toner with the photoelectric switch 23, and arouses an operator's attention by preventing the cover from being locked in place. However, the structure of the toner collecting apparatus becomes complicated and the manufacturing cost increases, since the detection of the toner collecting container's presence and the detection of the toner collecting container's filled up state are done with separate mechanisms independently.